LED Pars - Recommendations Please...

[gregog]

Morning All,

Been asked to purchase some LED Pars, so I will have to succumb to them!

 

They are to be used in a Studio Theatre Space, and will only ever be used for rear lighting and side lighting (from gantry). The 'stage space' is approx 5m wide by 4m deep. I don't expect to cover this entire depth from rear lighting. The suggestion of colour should suffice. The height of the IWB's is approx 5 metres again.

 

Ideally, I would like RGBA.

 

I have been looking at the Chauvet SlimPAR Pro RGBA. Though, at the height, I'm not sure if the spread of this unit will be sufficient to get an even wash. I am also aware that often LED units light is so intense, that they are often unable to be used passed 50% intensity. I'd like to avoid this, if possible, as they will be operated by novices and children, for the most part!

 

If anyone could advise and give some recommendations on units, that would be great. I don't want to go for cheap, budget units, and do have a reasonable budget. Given the amount of units I think I'll need, though, I don't think it's going to be too expensive!

 

Many, many thanks in advance for you help,

Gregog

[timsabre]

The chauvet pars are very good for the price, they seem to have smoother dimming than other units in that price region.

 

The beam angle is only 21 degrees so for a 5 metre throw the beam will be about 2 metres across when it hits the stage.

[top-cat]

There are many great options out there, at the moment my favourite brand for LED is Prolight - preferably the eLumen8 kit but the LEDJ kit is from the same manufacturer but to a lower spec. (eLumen8 also come with warranty).

 

They have recently brought out their 'Hex' LED Pars - that's R/G/B/W/A/UV so you really have the best possibilities for colours that you can get with LED.

 

You may want to consider fan noise when you make your choice. A lot of LED units have quite loud fans (high power LED gets surprisingly hot) and in rock n roll gigs or nightclubs this isn't much of an issue for obvious reasons, but for theatre - especially smaller theatres - it can be a problem especially where there are several units running. One common way to get around the problem of fan noise is to use outdoor (IP-rated) units. These can't have a fan because it would require a big hole on the outside, so they use heat sinks instead generally. Heat sinks do not make any noise http://www.blue-room.org.uk/public/style_emoticons/default/rolleyes.gif

 

Also, combining Tim's point about beam angle - and your concern about intensity - remember if you get an LED PAR which has a gel frame on the front, you can always insert frost, which will widen your beam and also take some of the glare off it.

[timsabre]

You may want to consider fan noise when you make your choice. A lot of LED units have quite loud fans (high power LED gets surprisingly hot) and in rock n roll gigs or nightclubs this isn't much of an issue for obvious reasons, but for theatre - especially smaller theatres - it can be a problem especially where there are several units running. One common way to get around the problem of fan noise is to use outdoor (IP-rated) units. These can't have a fan because it would require a big hole on the outside, so they use heat sinks instead generally. Heat sinks do not make any noise http://www.blue-room.org.uk/public/style_emoticons/default/rolleyes.gif

 

It's a good point, but fans seem to be becoming less common - the flat Chauvet units suggested don't have them, and I just got some of the cheap LEDJ 7Q5 flat pars and they don't have fans either.

[top-cat]

It's a good point, but fans seem to be becoming less common - the flat Chauvet units suggested don't have them, and I just got some of the cheap LEDJ 7Q5 flat pars and they don't have fans either.

 

Fair enough, I haven't bought a new fixture in a while! But yeah, the IP-rated units can just be a good way of getting something silent.

 

I have 40x 12x10W LED movers on my stage, the noise is really quite a lot!

[jason5d]

Have you thought about a pair of LED wash lights such as:

Adj dotz panel 2.4 and the dotz flood.

 

Ledj and Chauvet also make wash lights too,

I would use the dotz flood for your needs.

[gregog]

Hi All,

Thanks for the suggestions thus far.

 

What are the LEDJ units like for dimming? I've read good things about the Chauvet range when it comes to dimming, but as the LEDJ is seemingly marketed towards DJ's (who I assume wont be dimming too much) I want to be sure that they can dim smoothly, without flicker?

 

Has anyone used the units and can recommend or warn against?

 

Happy to look into floods, and have been looking at diufferent Pixelline units, cyc bars etc to the the rear line, but I think PARS would definitely best suit the sides.

 

Thanks so much,

Gregog

[top-cat]

What are the LEDJ units like for dimming? I've read good things about the Chauvet range when it comes to dimming, but as the LEDJ is seemingly marketed towards DJ's (who I assume wont be dimming too much) I want to be sure that they can dim smoothly, without flicker?

 

I don't know how the prices stack up, but if you can afford them, the eLumen8 products are from the same manufacturer but of a higher grade. As I said before they also, unlike the LEDJ kit, come with a manufacturers warranty.

 

I wouldn't say that "LEDJ" as a brand name means they're only marketed towards people who don't need dimming! To be honest with most lower-end LED you will find that the dimming is far from linear, many of the eLumen8 products have options for different dimming curves which can improve the situation somewhat, and your desk may have options for that too.

[timsabre]

The LEDJ units (the recent ones anyway) don't flicker, but if you do a slow fade there are visible steps in the dimming when the level is near 0%. This can be bad in the theatre if you're washing a cyc and doing a slow sunrise or something, the stepping becomes very obtrusive and spoils the effect. For band/music use you won't even notice.

 

All the units in that price bracket have this problem, it's basically down to using 8-bit dimming and the way your eye perceives brightness.

[ianknight]

The LEDJ units (the recent ones anyway) don't flicker, but if you do a slow fade there are visible steps in the dimming when the level is near 0%. This can be bad in the theatre if you're washing a cyc and doing a slow sunrise or something, the stepping becomes very obtrusive and spoils the effect. For band/music use you won't even notice.

 

All the units in that price bracket have this problem, it's basically down to using 8-bit dimming and the way your eye perceives brightness.

 

Apparently it's also partly the function of making the PSU's "flicker free" for video by using faster refresh rates - the Elumen8 Tri 8 Pixel Batten is very snappy below 5%.

 

A customer we sold some to controlled the issue by attaching Neutral Density Gel over the battens which effectively shifted the curve for the dimming. Otherwise it's a lovely unit and we've sold a few dozen in to theatres and school stages - the coverage and intensity over a short throw is very impressive for the units price.

[timsabre]

Apparently it's also partly the function of making the PSU's "flicker free" for video by using faster refresh rates - the Elumen8 Tri 8 Pixel Batten is very snappy below 5%.

 

It sort of is, to make the device flicker free you have to increase the speed of the PWM dimming. The only way to do this (without using a faster processor) is to reduce the number of bits in the dimming, so you could do 12 bits at 100Hz refresh or 8 bits at 1.6KHz refresh.

The faster speed reduces flicker for cameras but makes the steps in the dimming bigger. Curiously even though all the dim steps are the same size, the eye can see the ones at the bottom much better than the ones at the top.

[top-cat]

The LEDJ units (the recent ones anyway) don't flicker, but if you do a slow fade there are visible steps in the dimming when the level is near 0%. This can be bad in the theatre if you're washing a cyc and doing a slow sunrise or something, the stepping becomes very obtrusive and spoils the effect. For band/music use you won't even notice.

 

All the units in that price bracket have this problem, it's basically down to using 8-bit dimming and the way your eye perceives brightness.

 

Apparently it's also partly the function of making the PSU's "flicker free" for video by using faster refresh rates - the Elumen8 Tri 8 Pixel Batten is very snappy below 5%.

 

A customer we sold some to controlled the issue by attaching Neutral Density Gel over the battens which effectively shifted the curve for the dimming. Otherwise it's a lovely unit and we've sold a few dozen in to theatres and school stages - the coverage and intensity over a short throw is very impressive for the units price.

 

Slightly off topic, I generally agree with your observation on that fixture, I have a dozen and they are offensively bright! They're really simple to set up and if you have a good effects generator on your controller it's very quick to set up some really nice looking effects on them.

 

Sadly, eLumen8 still have some work to go on their 'COB' (chip on board) LED fixtures. Whilst, for PAR Cans, I do generally prefer the single LED, COB design (it more accurately looks like a traditional fixture, as it only has one light source, not the 18 or whatever you get on most LED PARs) but it doesn't seem to do darker shades very well at all. (And of course, being 3ch RGB, the white is pretty ghastly). And the apart from the snappy dims at low levels, the lower intensities also introduce some horrid looking shades of colour. For instance, what is a very nice tungsten shade at 30%, is like mouldy mustard colour at 3!

[timsabre]

Sadly, eLumen8 still have some work to go on their 'COB' (chip on board) LED fixtures. Whilst, for PAR Cans, I do generally prefer the single LED, COB design (it more accurately looks like a traditional fixture, as it only has one light source, not the 18 or whatever you get on most LED PARs) but it doesn't seem to do darker shades very well at all.

 

The chinese RGB COB led modules are strange beasts, manufacturers are busy churning out white COB LEDs as every man and his dog is building floodlights with them in. The RGB ones are less common and for some reason the RGB dies they use have wishy washy colours, the red is sort of orangey, the blue is sort of cyany and the overall effect is not great. If you buy expensive COB LEDs from Ledengin the colours are very pure and nice so I don't know why the chinese ones are not.

[top-cat]

High power white LED chips I am quite down with. If you can get one of the 2 channel variety which let you blend 'cool white' and 'warm white', it's possible to roughly colour match them to your tungsten fixtures by shining them at a white wall and comparing the colour temperature.

 

By doing that, you can then use them with traditional lighting gel, to help match colours with your existing lantern stock if you're going to phase out tungsten over time. Although it does of course mean, at the end of the transition, you will still have to keep buying gel.

[alistermorton]

Even if you get it to look the same on a white wall, chances are you're going to find that the colours you get when you gel it up are not going to quite match the tungsten colours, as the spectrum has a different profile even if the perceived "colour temperature" about matches.